exploreyourself

Oh, God, this has the potential to turn into a holy war. It's like asking which is better, Macs or PCs. That said, it's still a valid question.

Here's my take: as long as you have good quality amps (flat frequency response, good distortion figures, etc) and are operating each amp within it's power envelope (not coming anywhere close to clipping) you shouldn't hear a difference!

There is no mystery to this stuff - I've been in a position for the last few years where I have access to test data for literally thousands of different amps, preamps, etc. The key, IMHO, to understanding why well-designed (this is important) amps sound different lies in three areas:

1. Do they really sound different - or do you just think so? Ive seen a number of double blind AB and ABX listening tests where amps were indistinguishable from one another as long as they were not total crap. If you know what you are listening to your brain will strive to hear a difference and often create one where it does not exist. It's a very powerful effect and I didn't really believe it until I experienced it myself and witnessed it in others.

2. Are you operating the amp within its power envelope? Music (particularly on well recorded albums that haven't been overly compressed) is extraordinarly dynamic. If you are listening at a volume that even remotely approaches "a bit loud" you will probably be shocked to know how much power it takes to reproduce a piano without inducing a bit of clipping in the amp. It's something on the order of 50W-100W, depending on the sensitivity of your speakers. I don't have the numbers in front of me right now, so please excuse this hand-wavy explaination.

Even very small amounts of clipping are detectable by the ear. Tube amps clip more gracefully than solid state amps - so if both amps are clipping the tube amp will sound better in those conditions. Accordingly, for the same perceived sound quality a tube amp can clip more than a solid state amp. When a solid state amp clips it literally cuts off (hence "clips") the peaks of the waveform. Tube amp clipping looks more like compression - sort of squeezing the waveform while keeping the same general shape. Be very wary of manufacturer's quote power outputs, especially on less expensive gear. This goes double for any sort of home theater receiver product. There are all kinds of games that can be played to grossly inflate an amp's power rating.

But, as long as you are using amps powerful enough for your sepakers, room size, and listening level this shouldn't come into play. But like I said above - it comes into play more often than most people suspect, I suspect.

3. Your speakers and the effect they have on the amp. Yes - your speakers effect what's going on in the amp in addition to the other way around. It's just a fact that, due to their design, solid state amps are way better at driving low impedance loads. If you have demanding speakers (electrically speaking, that is) you will almost certianly be better off with a sold state amp.

In the end - I'm a fan of any well designed amplifier. Pragmatically speaking - I recommend solid state amps when asked. They require much less maintenance (tube amps need the bias checked every so often, and you will have to replace tubes), and for the same sound quality you will spend much less on a solid state unit than you would have to for a tube amp. But, tube amps do look cool.

One final thing - guitar players and live bands often use tube amps. This is usually due to the distortion that the tubes introduce into the music. Many people find the sound of this distortion pleasing, which illustrates another point: it's as much about taste as anything else. But - there's a difference between deliberately introducing distortion during the performance/recording process and unintentionally introducing it during the playback. If you duplicate the distortion of the performance/recording process you will "double up" on the distortion and that's probably not what the artist intended. My goal is to be as original to the performance of the artist as possible. Otherwise it's like going to the museum with colored glasses - you might not mind the look but you aren't seeng the artist's work.